Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania: Partial Approval of PM-10 Implementation Plan for the Liberty Borough Area of Allegheny County

EPA is approving, in part, revisions to the Allegheny County portion for the Pennsylvania State Implementation Plan (SIP) prepared by the Allegheny County Health Department (ACHD) and formally submitted by the Pennsylvania Department of Environmental Protection (PADEP). PADEP submitted the SIP revisions, in general, to satisfy the Clean Air Act's (the Act's) requirements for control of particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM-10), and specifically, to satisfy the Act's requirements applicable to the Liberty Borough area of Allegheny County, which is classified as a moderate nonattainment area for the national ambient air quality standards (NAAQS) for PM-10. EPA is approving the regulatory portions the Commonwealth's submittals. EPA is deferring action, at this time, on the attainment demonstration and associated air quality analyses portion of one of the Commonwealth's submittals. This action is being taken under section 110 of the Act.